Charge-state resolved laser acceleration of gold ions to beyond 7 MeV/u.

In the past years, the interest in the laser-driven acceleration of heavy ions in the mass range of [Formula: see text] has been increasing due to promising application ideas like the fission-fusion nuclear reaction mechanism, aiming at the production of neutron-rich isotopes relevant for the astrophysical r-process nucleosynthesis. In this paper, we report on the laser acceleration of gold ions to beyond 7 MeV/u, exceeding for the first time an important prerequisite for this nuclear reaction scheme. Moreover, the gold ion charge states have been detected with an unprecedented resolution, which enables the separation of individual charge states up to 4 MeV/u. The recorded charge-state distributions show a remarkable dependency on the target foil thickness and differ from simulations, lacking a straight-forward explanation by the established ionization models.

Traumatic Brain Injury and Depression in a Community-Based Sample: A Cohort Study Across the Adult Life Span.

OBJECTIVES: To determine whether self-reported traumatic brain injuries (TBIs) are associated with "cases" of clinically significant depression in the general community. To examine interactions between variables previously linked to depression after a TBI. SETTING: Population-based community study (Canberra and Queanbeyan, Australia). PARTICIPANTS AND DESIGN: Three age cohorts: young, middle-aged, and older adults (aged 20-24, 40-44, and 60-64 years at baseline) randomly selected from the electoral roll and followed across 3 waves (4 years apart). A total of 7397, 6621, and 6042 people provided their TBI history in waves 1 to 3. MEASURES: Lifetime (TBIlifetime: sustained at any time since birth), recent (TBIrecent: in the preceding 4 years), and multiple (TBImultiple: more than 1) TBIs, current depression, and known risk factors for depression (age, sex, marital/employment status, prior history of depression, medical conditions, recent life events, alcohol consumption, social support, physical activity). RESULTS: Generalized estimating equations demonstrated a significant association between sustaining a TBI and experiencing clinically significant depression (cases), even after controlling for multiple demographic and health/lifestyle factors. CONCLUSION: There is an enduring association between depression and TBI, suggesting that, following a TBI, individuals should be monitored and supported to optimize their long-term psychological health.

Anxiety and comorbid depression following traumatic brain injury in a community-based sample of young, middle-aged and older adults.

BACKGROUND: Anxiety is common following a traumatic brain injury (TBI), but who is most at risk, and to what extent, is not well understood. METHODS: Longitudinal data from a randomly-selected community sample (Wave 1: 7397, Wave 2: 6621 and Wave 3: 6042) comprising three adult cohorts (young: 20-24 years of age, middle-aged: 40-44, older: 60-64), were analysed. The association between TBI history, anxiety and comorbid depression was assessed, controlling for age, sex, marital/employment status, medical conditions, recent life events, alcohol consumption, social support and physical activity. RESULTS: Thirteen percent of the sample had sustained a TBI by Wave 3, 35% of whom had sustained multiple TBIs. Cross-sectional analyses revealed that clinically-significant anxiety was more common in people who had sustained a TBI. Longitudinal analyses demonstrated an increased risk of anxiety post-TBI, even after controlling for potential demographic, health and psychosocial confounds. Anxiety was more common than depression, although 10% of those with a TBI experienced comorbid anxiety/depression. LIMITATIONS: TBIs were not medically confirmed and anxiety and depression were only assessed every four years by self-report, rather than clinical interview. Sample attrition resulted in the retention of healthier individuals at each wave. CONCLUSIONS: TBIs are associated with a lifelong increased risk of experiencing clinically-significant anxiety, highlighting the chronic nature of TBI sequelae. Positive lifestyle changes (e.g., increasing physical activity, reducing alcohol consumption) may decrease the risk of anxiety problems in the early years after a TBI. Comorbid anxiety and depression was common, indicating that both should be monitored and treated.

The impact of suicidality on health-related quality of life: A latent growth curve analysis of community-based data.

OBJECTIVE: The subjective burden of suicidality on mental and physical health-related quality of life (HRQoL) remains to be examined. Eight-year trajectories of mental and physical components of HRQoL were compared for suicidal and non-suicidal participants at baseline. The effect of poor mental and/or physical HRQoL on subsequent suicidality was also investigated. METHOD: Randomly-selected community data (W1=7485; W2=6715; W3=6133) were analysed with multivariate latent growth curve (LGC) and logistic regression models. RESULTS: Adjusted LGC modelling identified that baseline ideation was associated with poorer mental, but better physical HRQoL at baseline (b=-3.93, 95% CI=-4.75 to -3.12; b=1.38, 95% CI=0.53-2.23, respectively). However, ideation was associated with a declining physical HRQoL trajectory over 8 subsequent years (b=-0.88, 95% CI=-1.42 to -0.35). Poorer mental HRQoL was associated with higher odds of ideation onset (OR=0.98, 95% CI=0.96-0.99). LIMITATIONS: Frequency of data collection was four-yearly, while suicidality was reported for the previous 12-months; analyses did not control for physical health problems at baseline, baseline depression may have influenced physical QoL; suicidality was assessed with binary measures; and, prior analyses of attrition over time showed those with poorer health were less likely to continue participating in the study. CONCLUSIONS: Suicidality has differential longitudinal effects on mental and physical HRQoL. Findings emphasise the considerable subjective HRQoL burden upon suicidal individuals. HRQoL may be useful to compare relative social and economical impacts.

Prevalence of anxiety following adult traumatic brain injury: A meta-analysis comparing measures, samples and postinjury intervals.

OBJECTIVE: Anxiety following a traumatic brain injury (TBI) is a common problem; however, disparate prevalence estimates limit the clinical utility of research. The purpose of the current study was to examine how differences in methodological variables and sample characteristics impact on the prevalence of anxiety. METHOD: Data from 41 studies that examined either the prevalence of generalized anxiety disorder (GAD) diagnoses or clinically significant "cases" of self-reported anxiety following adult, nonpenetrating TBI were analyzed, and the impact of diagnostic criteria, measure, postinjury interval and injury severity was evaluated. RESULTS: Overall, 11% of people were diagnosed with GAD and 37% reported clinically significant levels of anxiety following TBI. Prevalence estimates varied for different diagnostic criteria (range: 2%-19%), interview schedules (range: 2%-28%), and self-report measures (range: 36%-50%). GAD and "cases" of anxiety were most prevalent 2 to 5 years postinjury. The rates of GAD increased with injury severity (mild: 11%, severe 15%), but "cases" decreased (mild: 53%, severe: 38%), although neither difference was significant. CONCLUSIONS: Anxiety is common after a TBI and ongoing monitoring and treatment should be provided. Methodological and sample characteristics should be clear and well-defined, as differences across studies (e.g., how anxiety is conceptualized, which measure is used, time since injury, injury severity) impact prevalence rates.

Changes in genetic and environmental influences on disordered eating between early and late adolescence: a longitudinal twin study.

BACKGROUND: We investigated the genetic and environmental contributions to disordered eating (DE) between early and late adolescence in order to determine whether different sources of heritability and environmental risk contributed to these peak times of emergence of eating disorders. METHOD: Adolescent female twins from the Australian Twin Registry were interviewed over the telephone with the Eating Disorder Examination (EDE). Data were collected at 12-15 and 16-19 years (wave 1: N = 699, 351 pairs; wave 3: N = 499, 247 pairs). Assessments also involved self-report measures related to negative life events and weight-related peer teasing. RESULTS: Unstandardized estimates from the bivariate Cholesky decomposition model showed both genetic influences and non-shared environmental influences increased over adolescence, but shared environmental influences decreased. While non-shared environmental sources active at ages 12-15 years continued to contribute at 16-19 years, new sources of both additive genetic and non-shared environmental risk were introduced at ages 16-19 years. Weight-related peer teasing in early-mid adolescence predicted increases of DE in later adolescence, while negative life events did not. CONCLUSIONS: Two-thirds of the heritable influence contributing to DE in late adolescence was unique to this age group. During late adolescence independent sources of genetic risk, as well as environmental influences are likely to be related in part to peer teasing, appear key antecedents in growth of DE.

Depression following adult, non-penetrating traumatic brain injury: a meta-analysis examining methodological variables and sample characteristics.

BACKGROUND: Depression is one of the most frequently reported psychological problems following TBI, however prevalence estimates vary widely. Methodological and sampling differences may explain some of this variability, but it is not known to what extent. METHODS: Data from 99 studies examining the prevalence of clinically diagnosed depression (MDD/dysthymia) and self-reports of depression (clinically significant cases or depression scale scores) following adult, non-penetrating TBI were analysed, taking into consideration diagnostic criteria, measure, post-injury interval, and injury severity. RESULTS: Overall, 27% of people were diagnosed with MDD/dysthymia following TBI and 38% reported clinically significant levels of depression when assessed with self-report scales. Estimates of MDD/dysthymia varied according to diagnostic criteria (ICD-10: 14%; DSM-IV: 25%; DSM-III: 47%) and injury severity (mild: 16%; severe: 30%). When self-report measures were used, the prevalence of clinically significant cases of depression differed between scales (HADS: 32%; CES-D: 48%) method of administration (phone: 26%; mail 46%), post-injury interval (range: 33-42%), and injury severity (mild: 64%; severe: 39%). CONCLUSION: Depression is very common after TBI and has the potential to impact on recovery and quality of life. However, the diagnostic criteria, measure, time post-injury and injury severity, all impact on prevalence rates and must therefore be considered for benchmarking purposes.

Analysis of expression and structure of the TSG101 gene in cervical cancer cells.

Human papillomavirus (HPV)-mediated transformation of human epithelial cells has been recognized as a multi-step process in which additional unknown factors and (epi)genetic events are required. The tumor susceptibility gene 101 (TSG101) was discovered in mouse NIH3T3 fibroblast cells as a gene whose functional knockout leads to transformation. TSG101 protein is involved in a variety of important biological functions, such as ubiquitination, transcriptional regulation, endosomal trafficking, virus budding, proliferation and cell survival. It is suggested that TSG101 is an important factor for maintaining cellular homeostasis and that perturbation of TSG101 functions leads to cell transformation. Interestingly, a recent report showed up- or down-regulation of TSG101 in several human malignancies. At present, the role of TSG101 in cervical tumorigenesis is unexplained. TSG101 expression in tumors, where carcinogenesis is connected with viral infection, and a mechanism of TSG101 expression regulation in cancer cells are also unknown. The aim of our study was to estimate the TSG101 mRNA and protein level in cervical cancer and non-tumor epithelial cells. We also analyzed the TSG101 coding and promoter sequence using the PCR-SSCP technique and methylation pattern of the TSG101 promoter. Our real-time PCR and Western blot analysis showed decreased TSG101 mRNA and protein level in cervical cancer tissue in comparison to normal (non-tumor) HPV(-) and HPV16(+) epithelial cells. Our results suggest that TSG101 down-regulation in cervical cancer cells is not regulated by genetic or epigenetic events. However, we detected novel single nucleotide polymorphisms in the promoter of this gene.

Substrate binding to a cyclodextrin glycosyltransferase and mutations increasing the gamma-cyclodextrin production.

Bacterial cyclodextrin glycosyltransferases use starch to produce cyclic maltooligosaccharides (cyclodextrins) which are of interest in various applications. The cyclization reaction gives rise to a spectrum of ring sizes consisting of predominantly six to eight glucosyl units. Using the enzyme from Bacillus circulans strain no. 8, binding studies have been performed with several substrates and analogues. The observed binding modes differ in detail, but agree in general with data on homologous enzymes. Based on these binding studies, two mutations were designed that changed the production spectrum from the predominant product beta-cyclodextrin of the wild-type enzyme towards gamma-cyclodextrin, which is of practical interest because it is rare and can encapsulate larger nonpolar compounds.

Structure of cyclodextrin glycosyltransferase complexed with a derivative of its main product beta-cyclodextrin.

Crystals of the inactive mutant Glu257-->Ala of cyclodextrin glycosyltransferase were soaked with the cyclodextrin (CD) derivative S-(alpha-D-glucopyranosyl)-6-thio-beta-CD. The structural analysis showed its beta-CD moiety with no density indication for the exocyclic glucosyl unit. For steric reasons, however, the position of this unit is restricted to be at only two of the seven glucosyl groups of beta-CD. The analysis indicated that the enzyme can cyclize branched alpha-glucans. The ligated beta-CD moiety revealed how the enzyme binds its predominant cyclic product. The conformation of the ligated beta-CD was intermediate between the more symmetrical conformation in beta-CD dodecahydrate crystals and the conformation of a bound linear alpha-glucan chain. Its scissile bond was displaced by 2.8 A from the position in linear alpha-glucans. Accordingly, the complex represents the situation after the cyclization reaction but before diffusion into the solvent, where a more symmetrical conformation is assumed, or the equivalent state in the reverse reaction. Furthermore, a unifying nomenclature for oligosaccharide-binding subsites in proteins is proposed.